Significance: Through the Peruvian Genome Project we generate and analyze the genomes of 280 individuals where the majority have >90% Native American ancestry and explore questions at the interface of evolutionary genetics, history, anthropology, and medicine. This is the most extensive sampling of high-coverage Native American and mestizo whole genomes to date. We estimate an initial peopling of Peru was rapid and began by 12,000 y ago. In addition, the mestizo populations exhibit admixture between Native American groups prior to their Spanish admixture and was likely influenced by the Inca Empire and Spanish conquest. Our results address important Native American population history questions and establish a dataset beneficial to address the underrepresentation of Native American ancestry in sequencing studies.

J. Neurochem. (2012) 120, 302–313. The molecule responsible for the enzyme activity plasma membrane (PM) aminophospholipid translocase (APLT), which catalyzes phosphatidylserine (PS) translocation from the outer to the inner leaflet of the plasma membrane, is unknown in mammals. A Caenorhabditis elegans study has shown that ablation of transbilayer amphipath transporter‐1 (TAT‐1), which is an ortholog of a mammalian P‐type ATPase, Atp8a1, causes PS externalization in the germ cells. We demonstrate here that the hippocampal cells of the dentate gyrus, and Cornu Ammonis (CA1, CA3) in mice lacking Atp8a1 exhibit a dramatic increase in PS externalization. Although their hippocampi showed no abnormal morphology or heightened apoptosis, these mice displayed increased activity and a marked deficiency in hippocampus‐dependent learning, but no hyper‐anxiety. Such observations indicate that Atp8a1 plays a crucial role in PM‐APLT activity in the neuronal cells. In corroboration, ectopic expression of Atp8a1 but not its close homolog, Atp8a2, caused an increase in the population (V_max) of PM‐APLT without any change in its signature parameter K_m in the neuronal N18 cells. Conversely, expression of a P‐type phosphorylation‐site mutant of Atp8a1 (Atp8a1*) caused a decrease in V_max of PM‐APLT without significantly altering its K_m. The Atp8a1*‐expressing N18 cells also exhibited PS externalization without apoptosis. Together, our data strongly indicate that Atp8a1 plays a central role in the PM‐APLT activity of some mammalian cells, such as the neuronal N18 and hippocampal cells.

Western South America was one of the worldwide cradles of civilization. The well-known Inca Empire was the tip of the iceberg of an evolutionary process that started 11,000 to 14,000 years ago. Genetic data from 18 Peruvian populations reveal the following: 1) The between-population homogenization of the central southern Andes and its differentiation with respect to Amazonian populations of similar latitudes do not extend northward. Instead, longitudinal gene flow between the northern coast of Peru, Andes, and Amazonia accompanied cultural and socioeconomic interactions revealed by archeology. This pattern recapitulates the environmental and cultural differentiation between the fertile north, where altitudes are lower, and the arid south, where the Andes are higher, acting as a genetic barrier between the sharply different environments of the Andes and Amazonia. 2) The genetic homogenization between the populations of the arid Andes is not only due to migrations during the Inca Empire or the subsequent colonial period. It started at least during the earlier expansion of the Wari Empire (600 to 1,000 years before present). 3) This demographic history allowed for cases of positive natural selection in the high and arid Andes vs. the low Amazon tropical forest: in the Andes, a putative enhancer in HAND2-AS1 (heart and neural crest derivatives expressed 2 antisense RNA1, a noncoding gene related to cardiovascular function) and rs269868-C/Ser1067 in DUOX2 (dual oxidase 2, related to thyroid function and innate immunity) genes and, in the Amazon, the gene encoding for the CD45 protein, essential for antigen recognition by T and B lymphocytes in viral–host interaction. Significance Native Americans are neglected in human genetics studies, despite recent interest in the study of ancient DNA of their ancestors. Our findings on Andean and Amazonian populations exemplify how the current pattern of genetic diversity in human populations is influenced by the interaction of history and environment. In the present case, this pattern is influenced by 1) altitudinal and climatic differences among the northern, lower, and fertile Andes versus the southern, higher, and arid Andes and 2) the sharp differences between the Andean highlands and the Amazon lowlands, where natural selection and other evolutionary forces acted for millennia, shaping differences in the frequencies of genetic variants related to immune response, drug response, and cardiovascular and hematological functions.

Peruvians currently preserve in their DNA the history of 2.5 million years of human evolution and 150,000 years of migration from Africa to Peru or the Americas. The development of Genetics and Genomics in the clinical and academic field is shown in this review.

The emergence of multidrug-resistant strains is a major health problem especially for countries with high TB incidence such as Peru. In this study, we evaluated High Resolution Melting (HRM) assay in Peruvian isolates for the detection of mutations within rpoB, katG genes and promoter region inhA to determine isoniazid and rifampicin resistance in Mycobacterium tuberculosis (Mtb). DNA samples extracted from a total of 167 clinical isolates of Mtb, 89 drug-sensitive and 78 multidrug-resistant, were blindly analyzed by HRM analysis and verified by DNA sequencing. The HRM analysis generated patterns that were specific to distinguish between sensitive and resistance isolates. The sensitivity and specificity of the HRM assays in comparison with drug susceptibility testing (DST) for detection of rifampicin resistance were 98.7 % and 97.5 %, and for isoniazid resistance were 98.7 % and 100 %. This study suggests that HRM Analysis could help with rapid diagnosis of MDR-TB cases in Peru.